MIDTERM 2

Question 1

What are primary areas of the cortex?

Answer 1

They receive “raw data” in various stages of pre-processing

Question 2

What are association areas of the cortex?

Answer 2

Integrate information to make sense of the world
Unimodal: Deals with one modality only, ex. sensory association area
Polymodal/heteromodal: integrates several modalities into one experience

Question 3

What determines the dominant hemisphere

Answer 3

By the language areas (not handedness)

Question 4

What is the revelance of cellular architechture and cortical architecture of the brain?

Answer 4

They correlate to each other, ie. cellular architecture is related to the functional areas of the brain

Question 5

What are the 3 types of subcortical fibres?

Answer 5

Commissural: connect hemispheres
Projection: project up/down
Association: connect within hemisphere

Question 6

Draw and label the internal capsule

Answer 6

(check cortex lecture, slide 15)

Question 7

Draw and label subcortical fibres of the brain:
- superior longitudinal fasciculus + arcuate fasciculus
- inferior fronto-occipital fasciculus + uncinate fasciculus
- cingulum
- arcuate fibres
- corpus callosum
- internal capsule
- optic radiations

Answer 7

(check cortex lecture slide 12 + slide 14)

Question 8

What are the differences of transthalamic connections and corticocortical connections?

Answer 8

Transthalamic: connections between the thalamus and association cortices, rapid conduction of signals, less “noise”

Corticocortical: connections between association cortices, relatively slower, makes more “noise”

Question 9

What is on the medial side of the motor homounculus?

Answer 9

Areas controlling the toes, knees, hips, trunk

Question 10

Which part of the thalamus is involved in motor processing?

Answer 10

Ventral anterior + Ventral lateral

Question 11

What happens with a lesion to the primary motor area?

Answer 11

Paralysis

Question 12

What happens with a lesion to the motor association area?

Answer 12

Apraxia

Question 13

What parts of the thalamus is involved in sensory processing?

Answer 13

Ventral posterolateral + Ventral posteromedial

Question 14

What happens when there is a lesion to the primary sensory area?

Answer 14

Poor localization of sensory stimuli

Question 15

What happens when there is a lesion to the sensory association area?

Answer 15

Tactile agnosia: inability to interpret significance of sensory information

Astereognosis: inability to recognize an object placed in the hand

Question 16

Which part of the thalamus is involved in hearing?

Answer 16

medial geniculate nucleus

Question 17

Which part of the thalamus is involved in seeing?

Answer 17

lateral geniculate nucleus

Question 18

What are the parietal association areas involved in, and how are they different in each hemisphere?

Answer 18

Involved in ATTENTION, AWARENESS OF SELF AND EXTRAPERSONAL SPACE

Dominant (left) hemisphere: attention/awareness of right side
Non-dominant (right) hemisphere: attention/awareness of left side AND right side

Question 18

What happens when there is a lesion in the non-dominant hemisphere of the parietal association areas? What are 2 tasks to test this condition?

Answer 18

Spatial neglect

2 tasks: star cancellation and copying

Question 18

What are the temporal association areas involved in?

Answer 18

Recognition

Question 18

What happens when there is a lesion in the medial temporal lobe?

Answer 18

Prosopagnosia: inability to recognize faces

Question 18

Explain what the “classic” model for language is?

Answer 18

Language involves only Broca’s area and Wernicke’s area, along with the connection between them (arcuate fasciculus)

Question 19

What are the frontal association areas involved in?

Answer 19

Social behaviour, executive function, directing + maintaining attention

Question 19

What is Broca’s area responsible for and how does it differ between hemispheres?

Answer 19

Responsible for production of language

Found to produce language mainly in the dominant hemisphere. Also in the non-dom hemisphere for prosody and tone.

Question 20

What happens when there is a lesion to Broca’s area?

Answer 20

Motor aphasia
(normal comprehension, impaired naming + repetition + fluency)

Question 21

What is Wernicke’s area responsible for and how does it differ between hemispheres?

Answer 21

Responsible for understanding language

The function is the same for both hemispheres

Question 22

What happens when there is a lesion to Wernicke’s area?

Answer 22

Sensory aphasia
(normal fluency, impaired comprehension + naming + repetition)

Question 23

What is the arcuate fasciculus responsible for in language and how does it differ between hemispheres?

Answer 23

Responsible for linking language production to understanding

Function is same in both hemispheres

Question 24

What happens when there is a lesion to the arcuate fasciculus?

Answer 24

Conduction aphasia
(normal comprehension + fluency, impaired naming + repetition)

Question 25

What are 3 key subcortical structures involved in language?

Answer 25

Basal ganglia
Cerebellum
Thalamus

Question 25

What is the dual stream model of language?

Answer 25

Dorsal stream: Frontal lobe -> spatial processing, sensorimotor integration; mapping phonological information onto articulatory motor representations
- Left dominant

Ventral stream: Temporal lobe -> Speech recognition and representation of lexical concepts (flour vs. flower)
- Bilaterally distributed

Question 26

What fibre tracts are apart of the “bottleneck of converging fibre tracts”?

Answer 26

Uncinate fasciculus
Inferior fronto-occipital fasciculus
Anterior thalamic radiations

Question 27

Due to refraction of the corena and lens, images on the retina are…

Answer 27

inverted and reversed

Question 28

What is the difference between the refraction power of the cornea and lens?

Answer 28

Cornea has greater refractive power, but lens can change its shape

Question 29

What are the 3 layers of the eye?

Answer 29

Retina: neural layer
Choroid: vascular layer
Sclera: connective layer

Question 30

What are 3 specialized area of the eye?

Answer 30

Fovea: place of highest visual acuity
Macula: area surrounding the fovea
Optic disc: head of optic nerve, where the blind spot is

Question 31

What are characteristics of rods?

Answer 31

Photoreceptors containing rhodopsin
- extremely sensitive to light
- active during dusk and nighttime
- 120 million in retina

Question 32

Describe the distribution of photoreceptors in the retina

Answer 32

Central retina: more cones -> better visual acuity
Peripheral retina: more rods -> better detection of movement

Question 33

What are characteristics of cones?

Answer 33

Photoreceptors containing iodopsin
- sensitive to red, green, and blue colour vision
- less sensitive to light than rods
- better visual acuity
- 6 million in retina

Question 34

Draw and label the visual pathway

Answer 34

(answer on visual system lecture, slide 16 + 17)

Question 35

Draw the projections of the upper, middle, and lower visual fields to the primary visual cortex

Answer 35

(ans in visual system lecture, slide 18)

Question 36

What is stereopsis?

Answer 36

depth perception

Question 37

What is the dorsal pathway of vision?

Answer 37

“Where and how”: interpreting spatial information (location, motion)

Question 38

What is the ventral pathway of vision?

Answer 38

“What”: interpreting object characteristics (colour, shape, patterns)

Question 39

What happens if there is a lesion in the dorsal pathway of vision?

Answer 39

Issues with navigation, object manipulation

Question 40

What happens if there is a lesion in the ventral pathway in vision?

Answer 40

Issues with object recognition, discrimination, visual orientation